Telephone-exchange system and apparatus.



No. 645,402; Patnted Mar. 13, I900.

. z. MILLER. TELEPHONE EXCHANGE SYSTEM AND APPARATUS.

(Applicatidq med Dec. 12, 1899.) '(No Model.) '3 Shee ts-S-haet l.

Inwzztan efizz Z Miller THE NORRIS vcrzns cu. worouma. WASHlNGTU-L n. c.

No. 645,402. Patented Mar. I3, I900.

J. 2. MILLER.

TELEPHONE EXCHANGE SYSTEM AND APPARATUS. (Application filed Dec. 12, 199. (No Model.) 3 Sheqts-Sheef 2,

No. 645,402. Patented Mar. l 3, I900. J. Z. MILLER.

TELEPHONE EXCHANGE SYSTEM AND APPARATUS. (Application filed Dec. 12, 1899.

(No Model.) 3 Sheets-Sheet 3.

ZZ ZZZZ .fl i jj-fo .Mzller w 7 M UNITED STATES JOHN Z. MILLER,

PATENT EEicE.

TELEPHONE-EXCHANGE SYSTEM AND APPARATUS.

SPECIFICATION forming part of Letters Patent No. 645,402, dated March 13, 1900. Application filed December 12, 1899. Serial No. 740,082. (No model.)

To all whom, it may concern.-

Be it known that 1, JOHN Z. MILLER, a citizen of the United States, residing at Erie, in the county of Erie and State of Pennsylvania, have invented new and useful Improvements in Telephone-Exchange Systems and Apparatus, of which the following is a specification;

My invention relates to telephone-exchange systems and apparatus, one object of the same being to provide means whereby a visual busysignal may be automatically given by the act of connecting up two subscribers, which signal will be maintained in operative position until the connection is removed.

A further object of the invention is to provide means for preventing the return of the annunciator-call drops to their normal positions after actuation until the call has been answered.

Other objects of the invention will hereinafter appear.

The invention consists of a telephone-exchange system comprising busy-signal drops at the central station for each subscriber and means thrown into operation by the act of connecting together two of said subscribers for actuating the busy-signal drops thereof.

The invention also consists of an annunciator comprising two magnets, one of which is connected with the line-circuit and the other with a circuit from alocal battery, a call-drop, a busy-signal drop, a detent controlled by the magnet in said line-circuit for maintaining said call-drop in its normal position, and connections between the armature of the magnet in said local circuit and said busy-signal drop for exposing the latter when said magnet is energized.

The invention also consists in certain features and details of construction and combinations of parts, which will be hereinafter more fully described and claimed.

In the drawings forming part of this specification, Figure 1 is a diagrammatic view illustrative of the invention. Fig. 2 is a front elevation of one of the annunciators, showing the parts of the same in their normal positions. Fig. 3 is a section on the line 3 3 of Fig. 2 looking to the right. Fig. 4 is a section on the line 4 4 of Fig. 2 looking to the left.

Fig. 5 is a plan view of the operatingroom. Fig. 6 is a sectional side elevation of a modified form of my annunciator, and Fig. 7 is a front elevation of the same.

Like reference letters and numerals indicate" like parts in the different views.

In Fig. 1 of the drawings 1 have shown the circuit connections between the telephones of two subscribers, with the corresponding multiple jacks and annunciators used in connection therewith. It is obvious, however, that at the central station through which the telephones of the two subscribers are connected there will be the regular switchboard and bank of annunciators, by which any two subscribersmaybeconnectedup. Fromthetelephone lat station A lead the line-wires 2 and 3,the same being connected, respectively,with the spring contact-strips 4 and 5 of the multiple jack 6 at the central station. Leading from the line-wires 2 and 3 in the central station are the wires 7 and 8, connected with the magnet 9, forming part of the annunciator 10. From the telephone 11 at station B lead the line-wires 12 13 to the spring-contacts 14 and 15, respectively, of the multiple jack 16 at the central station. Bridged across the line-circuit 12 13 are the circuit-wires 17 18, leading to the magnet 19, forming part of the annunciator 20. Between the contact-springs4 and 5 of the jack 6 are located contact-springs 21 22, the latter of whichis connected, through wires 23 and 24, with one pole of a local battery 25 and the former of which is connected, through the wire 26, with the magnet 27, forming part of the annunciator 10. From the magnet 27 lead the wires 28 and 29 to the other pole of the local battery 25. Between the contact-springs 14 15 of the jack 16 are contact-springs 30 and 31, the latter of which is connected, through the wires 32 and 23, with one pole of the local battery 25 and the former of which is connected, through the wire 33, with the coil of a magnet 34, forming part of the annunciator 20. From the magnet 34 leads the wire 35, which is connected, through the wires 28 and 29, with the other pole of the local battery 25.

From the foregoing description it will be seen that the magnets 9 and 19 of the annunciators 10 and 20 are in multiple with the linecircuits 2 and 3 and 12 and 13, respectively,

and that the coils of the magnets 27 and 34 are each in separate circuits from the local battery 25, which circuits are normally open at the jacks 6 and 16, respectively.

The circuits between the telephones 1 and 11 and the local circuits referred to are adapted to be closed simultaneously by plugs 36 and 37 at opposite ends of the connectingcord. Each of these plugs is formed with a wedge-shaped end 38, which is adapted when inserted into the jack to close the circuit be tween the contacts 21 and 22 or 30 and 31. The wedge-shaped end 38 is of conducting material and is separated from the remainder of the plug by a block 39 of insulating material. At the rear of the block 39 is the strip 40 of conducting material, separated by a block 41 of insulating material from the conducting-strip 42. On the latter is secu red the insulating-handle 43 of the plug. The wires 44 45 of the cord-circuit lead, respectively, from the strips 42 and 40 of the plug 36, through the wires 46 47, to the contact-springs 48 49, as shown. The wires 50 51 of the cordcircuit lead, respectively, from the strips 42 and 40 of the plug 37 to the spring-contacts 52 and The free ends of the contacts 52 and 53 are formed with curved extensions 54 55, and at the rear of said extensions said contacts are provided with lugs 56 57, adapted when said contacts are spread to engage the contacts 58 59, respectively. The contacts 58 59 are connected, through the wires 60 and 61, with the generator 62. The wires 46 and 47 heretofore referred to, are also connected at their ends opposite the contacts 48 and 49 with the contacts 63 64, the latter being formed with curved extensions 65 66, similar to the extensions 54 and 55 on the contacts 52 53. The contacts 63 and 64 are also provided with laterally projecting lugs 67 68, which are adapted to engage the contacts 69 70, connected, respectively, through the wires 71 72, with the operators telephone 73. In multiple with the cord-circuit 46 47, through a high resistance '74, is a ring-off drop or annunciator 75. Cooperating with the extensions 54 and 55of the contacts 52 and 53 and with the extensions 65 and 66 of the contacts 63 and 64 is a movable ball 76, forming part of a switch in the connecting-cord.

The annunciators 10 and 20, heretofore referred to, as well as the other annunciators in the bank at the central station, are identical with each other, the same being illustrated in detail in Figs. 2, 3, and4 of the drawings. As illustrated in said figures, the coil of the magnet 9 is bridged across the line-circuit through the Wires 7 and 8. The armature 77 of said magnetis pivoted to a bar 78, secured to the magnet-frame, and carries a detent 79, as clearly shown in Fig. 3 of the drawings. The said detent consists of a rod or wire secured to the armature 77 and extending forwardly therefrom, the same acting by gravity to maintain the armature 77 away from the pole of the magnet 9. The said rod projects through an opening 80 in the face-plate 81 of the annunciator and is adapted to engage a tooth or shoulder 82 on adrop or diaphragm 83, pivotally mounted upon a stud or projection 84. The upward movement of the drop 83 is limited by a stop 85, and the downward movement thereof is limited by a stop 86. The drop 83 is preferably constructed of a sheet of opaque metal having a blank outer surface, painted, for example, black, and the normal position of said drop is as shown in Figs. 2, 3, and 4that is, raisedand the same is held in raised position by the engagement of the detent 79 with the shoulder 82 thereon. Behind the drop 83, when the latter is in its normal raised position, is a plate 87, containing the number of the annunciator which corresponds with the number of the subscriber to whose telephoneesaid annunciator belongs. When the magnet 9 is energized, the armature 77 thereof is drawn toward the pole of said magnet. The detent 79 is raised, thereby releasing the drop 83, and the latter falls by gravity, exposing the numher on the plate 87. The number on said plate is, for example, black on a white ground.

The magnet 27, which is in thecircuit from the local battery 25 through the wires 26 and 28, has a pivotally-mounted pendent armature 88, the latter having a weighted extension 89 thereon. Extending forwardly from the armature 88 is an arm 90, the front end of which projects through a slot or opening 91 in the face-plate 81 of the annunciator.

It also extends through an elongated slot 92 of a busy-signal drop 93, pivotally mounted on the stud 84in front of the drop 83. The extension 89 tends to counterbalance the arm 90, Whose weight holds the armature 88 away from the pole of the magnet 27. The stops and 86, heretofore referred to, serve to limit the upward and downward movements of the drop 93, as well as the similar movements of the drop 83. When the magnet 27 is energized, the armature 88 will be drawn toward the pole thereof, moving upwardly the rod 90, which carries with it the drop 93. As long as the magnet 27 remains active said drop 93 remains in its raised position; but as soon as said magnet 27 is deenergized the drop 93 falls by gravity to its normal position, which is as shown in Figs. 2, 3, and 4 of the drawings. When the drops 83 and 93 are in their lowermost positions, they lie within a recess or pocket 94 and are covered by the front wall 95 thereof. The front face of the drop 93 has a number on it corresponding to the number on the plate 87; but said number or the background thereof is of a distinctive color. I prefer, as stated heretofore, to make the number on the plate 87 in black on a White background and prefer to make the number on the drop 93 in white on a red background. The particular colors of these numbers, however, or the background on which they are placed are not material to my invention, and I do not wishto be limited to the construction which is stated to be the one which I prefer. It is merely necessary that there should be some visual distinction between the number on the plate 87 and that upon the drop 93.

In Fig. 5 of the drawings is illustrated the general arrangement of the operating-room 96, representing a bank of drops 97, the operators sections, including the jacks, plugs, operator's'telephone, and talking-circuits. It will be observed that the operators sections are on opposite sides of the room from the bank of drops and that the latter are out of reach of the former, although they are in plain view.

The operation of my improved system and apparatus is as follows: If subscriber A rings up the central station, the circuit is closed through the magnet 9 of As annunciator in the central station. WVhen said magnet 9 is energized, the armature 77 thereof is attracted toward said magnet,which through the connections described elevates deteut 79 and releases the drop 83. When said drop is released, it falls down into recess or pocket 94 and exposes the number on the plate 87 which corresponds to the number of As telephone. The proper operator answers the call by inserting the plug 36 into one of the multiple jacks 6 connected with As telephone, which action, as shown in Fig. 1 of the drawings, closes the circuit from the local-battery 25 at the contacts 21 and 22 through the magnet 27 of annunciator 10 and also closes the cordcircuit between the contacts 4 and 40 and 5 and 42. When the magnet 27 is energized in the manner described, the armature 88 thereof is moved forwardly, causing the upward movement of the rod 90, connected with said armature, and a corresponding movement of the drop 93. As long as the plug 36 remains in the jack 6 the circuit from the local battery is closed, the magnet 27 remains energized, and the drop 93 remains in its raised position. This exposes on the annunciator 10 the red number on the drop 93, indicating that the line is busy through telephone A. The operator now moves the ball 76, forming a part of the switch, in the cord, so as to spread the contacts 63 and 64 and throw the lugs 67 and 68 into engagement with the contacts 69 and 70. When this is done, the operators telephone 7 3-is connected with subscriber As telephone, and the message sent by A may be received by the operator. If A asks to be connected with B, the ball 76, forming part of the switch, is moved to the left, spreading the contacts 52 and 53, separating them from the contacts 48 and 49, and bringing them into contact through the lugs 56 and 57 with the contacts 58 and 59. At the same time plug 37 is inserted into one of the multiple jacks 16, connected with the circuit through telephone B. The generator 62 is now in circuit with the telephone of subscriber B and the proper call is sent in. The operator then moves the ball 76, forming part of the cordswitch, into the position shown in Fig. 1 of the drawings, closing the cord-circuit through the contacts 48 and 52 and 49 and 53. Subscribers A and B are now connected with each other and conversation may be carried on. When the plug 37 is inserted into jack 16, however, the circuit from the local battery 25 is closed at 30 and 31 through the magnet 34 of Bs annunciator 20. As magnet 34 and magnet 27 are identical with each other, it will be obvious that the busy-signal drop 93 of annunciator 20 will be exposed to view as soon as the local circuit through the magnet 34 is closed. The busy-signal drops 93 of both annunciators l0 and 20 will remain exposed as long as the plugs 36 and 37 remain in the jacks 6 and 16. As soon as they are removed, however, and the magnets 27 and 34 are denergized the drops 93 will return to their normal positions behind the front wall 95 of the pocket 94. It should be stated in this connection that the rod 90, which raises the drop 93, is also adapted to engage the drop 83 when the latter is in its lowermost position, so that when the drop 93 is raised the drop 83 will also be raised. When, however, the magnet 27 is deenergized and the drop 93 falls, the drop 83 will be held in its normal raised position by-the engagement of the detent 79 with the shoulder 82 thereon.

When either one of the subscribers A or B rings off, annunciator 75 in the connectingcord will be actuated, indicating to the operator that subscribers A and B have finished talking and that the plugs 36 and 37 should be removed from the jacks 6 and 16.

The ring-off drop 75 and the annunciators 10 and 20 are bridged across from the cord and line circuits, respectively, but through high resistances, so that they do not affect the talking-circuits.

From the foregoing description it will be observed that a glance of the eye is all that is necessary to tell whether a line is in use or not instead of a motion of the hand, as in the ordinary busy test. The busy-signal drops remain in view as long as the plugs are in the corresponding jacks. The said drops are thus under the control of the operator. When the subscribers have finished talking and ring off,the ring-off-drop connected across the cordcircuit is actuated in the usual manner as a signal to the operator to take down the connection; but as long as the plugs are in the jacks the lines show busy, and when the plugs are withdrawn from the jacks the red signal disappears and the drop shows blank, ready for another call from the subscriber. It can be seen by this arrangement that one operator is able to look after the whole system from any section at night or at times when there are few calls and that it allowsa better distribution of operators during slack times-say when there is only work enough to keep half the operators busy. One operator seated at any section can care for the incoming calls on any two or more sections of drops. It will also be seen that the operator cannot slight her work by replacing drops at busy times without answering the calls, as it is necessary to actually plug in on the line to replace the drops. A closer watch can thus be kept on the operators work than can be done with the ordinary switchboard. A further advantage in having the drops away from the operators arises when repairs are necessary. These may be easily made without interrupting the work of any operator, as the operator may take care of her particular section of drops from any other operators section. The facility with which repairs can be made at the various' operators sections will be obvious, for the operator can be transferred to another section and continue to look after her subscribers while repairs are being made at her own section. The flexibility of the system is a great advantage.

In the modified form of my invention shown in Figs. 6 and 7 of the drawings a call-drop 83 is pivotally mounted at its lower end upon lugs or cars 96, so that it is adapted to swing outwardly. The same is maintained in its normal or raised'position by the engagement of the detent '7 9 with the upper front edge thereof. The said detent is in the form of an arm havinga hook or engaging portion 97 at its forward end projecting through the slot or opening in the face-plate 81 of the annunciator and connected at its rear end to the armature '77 of the magnet 9, which armature is itself pivoted upon a bracket or support 78. The armature 98 of the magnet 27 is pivotally mounted upon the support 99 and has connected with it the arm which extends forwardly therefrom and projects through the slot or opening 91 in the faceplate of the annunciator. It carries at its forward end the busy-signal drop 93, which is rigidly connected thereto and is adapted when the armature 98 is actuated to be elevated to a point in front of the call-drop 83 Said armature 98 is also provided with an adj ustable counterbalance-weight 100 for a purpose similar to the weighted extension ,89 in the preferred form of my invention. When the drops 83 and 93 are in their lowermost positions, they lie with-in the pocket 94, whose front wall flares outwardly, as shown. The operation of this form of my invention is identical with that of the preferred form.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a telephone-exchange system, a calldrop, a busy-signal drop movable in front of the same, and means thrown into operation by the act of connecting together two subscribers for actuating said busy-signal drop.

2. In a telephone-exchange system, a calldrop and a busy-signal drop for each subscriber, and means thrown into operation by the act of connecting together two subscribers for actuating the busy-signal drops of said subscribers and moving the same in front of the call-drops thereof.

3. In a telephone-exchange system, a calldrop, a busy-signal drop movable in front of the same, and means for automatically throwing said busy-signal drop into operation when two subscribers are connected together.

4. In a telephone-exchange system, jacks having call-drops and busy-signal drops, the

latter movable in front of the former and adapted to cover the same, plugs and cords for connecting together two subscribers, and means actuated by the insertion of said plugs into said jacks for throwing into operation the busysignal drops of the corresponding subscribers an nunciators and for maintaining said drops in operative position until said plugs are removed.

6. In a telephone-exchange system, jacks connected respectively with the different subscribers, annunciators for each subscriber having call-drops and busy-signal drops, the latter movable in front of the former-and adapted to cover the same, means actuated from the subscribers stations for throwing said call-drops into operation, plugs and'cords for connecting together two subscribers, and means actuated by the insertion of said plugs into said jacks for throwing into operation the busy-signal drops of the corresponding subscribers annunciators.

7. In a telephone-exchange system, jacks connected respectively with the difierent subscribers, annunciators for each subscriber having call-drops and busy-signal drops, the latter being located in front of the former, means actuated from the subscribers stations for throwing said call-drops into operation, plugs and cords for connecting together two subscribers, and means actuated by the insertion of said plugs into said jacks for throwing into operation the busy-signal drops of the corresponding subscribers annunciators and forreturning the call-drops of the corresponding subscribers annunciators to their normal positions.

8. In a telephone-exchange system, jacks connected respectively with the different subscribers, annunciators for each subscriber having call-drops and busy-signal drops, the latter movable in front of the former, magnets in multiple with the line-circuits for actuating the call-drops, magnets in a circuit from a local battery for actuating said busysignal drops and covering the call-drops thereby, the local-battery circuits being normally open through said jacks, and plugs and cords for connecting together two subscribers, said plugs, when inserted in said jacks, being adapted to close the circuits of the local battery through the busy-signal-drop-actuating magnets of the corresponding subscribers annunciators,as and for the purpose set forth.

9'. In a telephone-exchange system, an annunciator comprising two magnets, one of which is connected with the line-circuit and the other with a circuit from a localbattery, a call-drop, a busy-signal drop movable in front of said call-drop, a detent controlled by the magnet in said line-circuit for maintaining said call-drop in its normal position, and connections between the armature of the magnet in said local circuit and said busy-signal drop for exposing the latter when said magnet is energized.

10. In atelephone-exchange system, an an nunciator having a designating number or character thereon, a call-drop adapted, when in its normal position, to cover said number, a normally-covered busy-signal drop adapted to be moved in front of said call-drop and containing a number or character corresponding to the number or character on said annunciator, but distinguishable therefrom, a detent for maintaining said call-drop in its normal position, a magnet in the line-circuit for releasing said detent and allowing said call-drop to fall, a magnet in a circuit from a local battery, an armature therefor, and

connections between said armature and said Cil busy-signal drop for moving said drop into exposed position, as andfor the purpose set forth.

11. Ina telephoneexchange system, an annunciator having a designating number or character thereon, acall-drop adapted, when in its normal position, to cover said number, a normally-coveredbusy-signal drop adapted to be moved in front of said call-drop and containing a number or character corresponding to the number or character on said annunciator, but distinguishable therefrom, a magnet in the line-circuit, a piVotally-mounted armature therefor, a rod or bar connected to said armature and adapted to engage a shoulder on said call-drop for maintaining the latter in its normal position, a magnet in a normally-open circuit from a local battery, a pivotally-mounted armature therefor, and a rod or bar connected to the latter armature engaging said busy-signal drop for moving the same into exposed position in front of said call-drop and adapted to engage said call-drop for returning said call-drop to its normal position when said busy-signal drop is actuated.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

JOHN Z. MILLER.

Witnesses:

W. J. YOUNG, JAooB MADLEHNER. 

